Rarther, murine studies have corroborated the findings of Griesman et al. (Greisman et al., 1963), where challenge with LPS after infection does not lead to the production of pro-inflammatory cytokines such as TNF-α in mouse cell lines or in vivo (Telepnev et al., 2003, 2005; Bosio et al., 2007). This evidence concerns the gene TNF and infection.